Here is a revised version of our design, with quite a few changes.
First, we’ve added two mixing buttons per channel, one for Solo and one for Mute. We might add two more eventually (Select, Record), but I still need to give it some thoughts.
Second, we’ve added a BL64-1005MDA04 bargraph to visualize every channel. What’s nice about this component is the resolution level (64 LEDs) and the full 100 mm length, which perfectly matches the length of the motorized faders.
Third, on the advice of our friend Julien, we replaced our flimsy 12 V power connector with a more appropriate IEC connector. This forced us to move the 6.25 mm TRS connector for the headphones from back to front, which is a great improvement in and by itself.
Fourth, now that we have a frontplate component, we’ve decided to add two SD Card ports that could be used for audio recording. The reason for it is that our ES9102 analog-to-digital converters should be able to sample 8 stereo channels with a 32-bit resolution at a rate of 384 kHz, but this will generate massive amounts of data that won’t be possible to send over USB 2.0. Therefore, storing this data locally might be a better option. Or we’ll have to figure out a way to provide proper support for USB 3.0 from the Parrallella.
Last, but not least, we have worked on a rotating panel for our 32 jack chassis sockets. This allows us to keep our MacBook Pro 13″ footprint, while exposing all 32 ports on the faceplate whenever necessary. With this design, hinges would be mounted internally, and a mechanical button at the top right of the faceplate would be used to fold the panel back into the chassis.
This last element of our design justifies in and by itself the decision to keep two displays on the faceplate, instead of using just one. This will allow us to render contextual information on the two displays in direct relation to the positions of the faders, knobs, and ports. With this design, the backplate is 7 cm tall, while the frontplate is 3 cm tall. This should leave plenty of room internally to fit all the components that we’re planning to embed.
This is by far our most complex design, but also the one I like best…